The Texas Speed 427ci LSX Iron Short Block 1200 HP is built for buyers who need maximum strength in a high horsepower LS combination. It starts with the GM LSX iron block, a factory-strength foundation engineered for extreme boost, and adds a Texas Speed 4.00" forged crankshaft, Texas Speed 6.125" forged I-beam connecting rods and Wiseco forged pistons with upgraded Wiseco wrist pins, with ARP main studs clamping the bottom end.
Texas Speed rates the short block for up to 1200 horsepower and recommends it for large turbocharged, supercharged or nitrous-assisted builds in extreme street or race use. The pistons are offered in -4cc or -13cc dish versions so the compression ratio can be matched to the fuel and power adder planned, and the crankshaft carries a 58x reluctor wheel for Gen IV LS electronics. Each short block is designed, machined and assembled in-house by Texas Speed and ships with 12 quarts of break-in oil on an LS engine stand inside a crate.
Specifications
- Displacement: 427 cubic inches
- Block: GM LSX iron block
- Crankshaft: Texas Speed 4.00" stroke forged, 58x reluctor
- Connecting rods: Texas Speed 6.125" forged I-beam
- Pistons: Wiseco forged, -4cc or -13cc dish (selected at ordering), upgraded Wiseco wrist pins
- Main fasteners: ARP main studs
- Reluctor wheel: 58x for Gen IV LS electronics
- Power rating: 1200 HP per Texas Speed
- Intended use: Large turbocharged, supercharged or nitrous combinations, extreme street or race
- Assembly: Designed, machined and assembled in-house by Texas Speed
Kit Includes
- Texas Speed 427ci LSX short block with selected pistons
- ARP main studs (installed)
- Royal Purple 10W-30 break-in oil, 12 quarts (RYP-11487)
- Texas Speed LS engine stand with 3/8" drilled holes for shipping (TSP-Cradle)
- Shipping crate (TSP-SDCrateSB)
Ordering Options
Select the Piston option when ordering: Wiseco forged -4cc or -13cc dish pistons. The -4cc piston produces a higher compression ratio than the -13cc piston with the same cylinder heads and head gasket; Texas Speed offers both so the compression can be matched to the intended fuel and power adder.
Note: Final horsepower capability depends on supporting components, fuel system and tuning.
Vehicle Applications
Engine family: Gen III and Gen IV LS architecture on a GM LSX iron block. The 58x reluctor matches Gen IV LS engine management; vehicle list reflects the LS applications published by Texas Speed.
Chevrolet Camaro
- 1998 Chevrolet Camaro
- 1999 Chevrolet Camaro
- 2000 Chevrolet Camaro
- 2001 Chevrolet Camaro
- 2002 Chevrolet Camaro
- 2010 Chevrolet Camaro
- 2011 Chevrolet Camaro
- 2012 Chevrolet Camaro
- 2013 Chevrolet Camaro
- 2014 Chevrolet Camaro
- 2015 Chevrolet Camaro
Chevrolet Corvette
- 1997 Chevrolet Corvette
- 1998 Chevrolet Corvette
- 1999 Chevrolet Corvette
- 2000 Chevrolet Corvette
- 2001 Chevrolet Corvette
- 2002 Chevrolet Corvette
- 2003 Chevrolet Corvette
- 2004 Chevrolet Corvette
- 2005 Chevrolet Corvette
- 2006 Chevrolet Corvette
- 2007 Chevrolet Corvette
- 2008 Chevrolet Corvette
- 2009 Chevrolet Corvette
- 2010 Chevrolet Corvette
- 2011 Chevrolet Corvette
- 2012 Chevrolet Corvette
- 2013 Chevrolet Corvette
Cadillac CTS-V
- 2004 Cadillac CTS-V
- 2005 Cadillac CTS-V
- 2006 Cadillac CTS-V
- 2007 Cadillac CTS-V
- 2008 Cadillac CTS-V
- 2009 Cadillac CTS-V
- 2010 Cadillac CTS-V
- 2011 Cadillac CTS-V
- 2012 Cadillac CTS-V
- 2013 Cadillac CTS-V
- 2014 Cadillac CTS-V
- 2015 Cadillac CTS-V
Cadillac Escalade
- 2002 Cadillac Escalade
- 2003 Cadillac Escalade
- 2004 Cadillac Escalade
- 2005 Cadillac Escalade
- 2006 Cadillac Escalade
- 2008 Cadillac Escalade
- 2009 Cadillac Escalade
- 2010 Cadillac Escalade
- 2011 Cadillac Escalade
- 2012 Cadillac Escalade
- 2013 Cadillac Escalade
- 2014 Cadillac Escalade
Pontiac Firebird
- 1998 Pontiac Firebird
- 1999 Pontiac Firebird
- 2000 Pontiac Firebird
- 2001 Pontiac Firebird
- 2002 Pontiac Firebird
Pontiac G8
- 2008 Pontiac G8
- 2009 Pontiac G8
Pontiac GTO
- 2004 Pontiac GTO
- 2005 Pontiac GTO
- 2006 Pontiac GTO
GMC Sierra 1500
- 1999 GMC Sierra 1500
- 2000 GMC Sierra 1500
- 2001 GMC Sierra 1500
- 2002 GMC Sierra 1500
- 2003 GMC Sierra 1500
- 2004 GMC Sierra 1500
- 2005 GMC Sierra 1500
- 2006 GMC Sierra 1500
- 2007 GMC Sierra 1500
- 2008 GMC Sierra 1500
- 2009 GMC Sierra 1500
- 2010 GMC Sierra 1500
- 2011 GMC Sierra 1500
- 2012 GMC Sierra 1500
- 2013 GMC Sierra 1500
GMC Sierra 2500
- 2001 GMC Sierra 2500
- 2002 GMC Sierra 2500
- 2003 GMC Sierra 2500
- 2004 GMC Sierra 2500
- 2005 GMC Sierra 2500
- 2006 GMC Sierra 2500
- 2007 GMC Sierra 2500
- 2009 GMC Sierra 2500
- 2010 GMC Sierra 2500
- 2011 GMC Sierra 2500
- 2012 GMC Sierra 2500
- 2013 GMC Sierra 2500
- 2014 GMC Sierra 2500
GMC Sierra 3500
- 2001 GMC Sierra 3500
- 2002 GMC Sierra 3500
- 2003 GMC Sierra 3500
- 2004 GMC Sierra 3500
- 2005 GMC Sierra 3500
- 2006 GMC Sierra 3500
- 2009 GMC Sierra 3500
- 2010 GMC Sierra 3500
- 2011 GMC Sierra 3500
- 2012 GMC Sierra 3500
- 2013 GMC Sierra 3500
- 2014 GMC Sierra 3500
Chevrolet Silverado 1500
- 1999 Chevrolet Silverado 1500
- 2000 Chevrolet Silverado 1500
- 2001 Chevrolet Silverado 1500
- 2002 Chevrolet Silverado 1500
- 2003 Chevrolet Silverado 1500
- 2004 Chevrolet Silverado 1500
- 2005 Chevrolet Silverado 1500
- 2006 Chevrolet Silverado 1500
- 2007 Chevrolet Silverado 1500
- 2008 Chevrolet Silverado 1500
- 2009 Chevrolet Silverado 1500
- 2010 Chevrolet Silverado 1500
- 2011 Chevrolet Silverado 1500
- 2012 Chevrolet Silverado 1500
- 2013 Chevrolet Silverado 1500
Chevrolet Silverado 2500
- 1999 Chevrolet Silverado 2500
- 2000 Chevrolet Silverado 2500
- 2001 Chevrolet Silverado 2500
- 2002 Chevrolet Silverado 2500
- 2003 Chevrolet Silverado 2500
- 2004 Chevrolet Silverado 2500
- 2005 Chevrolet Silverado 2500
- 2006 Chevrolet Silverado 2500
- 2007 Chevrolet Silverado 2500
- 2008 Chevrolet Silverado 2500
- 2009 Chevrolet Silverado 2500
- 2010 Chevrolet Silverado 2500
- 2011 Chevrolet Silverado 2500
- 2012 Chevrolet Silverado 2500
- 2013 Chevrolet Silverado 2500
- 2014 Chevrolet Silverado 2500
Chevrolet Silverado 3500
- 2001 Chevrolet Silverado 3500
- 2002 Chevrolet Silverado 3500
- 2003 Chevrolet Silverado 3500
- 2004 Chevrolet Silverado 3500
- 2005 Chevrolet Silverado 3500
- 2006 Chevrolet Silverado 3500
- 2007 Chevrolet Silverado 3500
- 2008 Chevrolet Silverado 3500
- 2009 Chevrolet Silverado 3500
- 2010 Chevrolet Silverado 3500
- 2011 Chevrolet Silverado 3500
- 2012 Chevrolet Silverado 3500
- 2013 Chevrolet Silverado 3500
- 2014 Chevrolet Silverado 3500
Chevrolet SS
- 2014 Chevrolet SS
- 2015 Chevrolet SS
- 2016 Chevrolet SS
- 2017 Chevrolet SS
Chevrolet Suburban
- 2000 Chevrolet Suburban
- 2001 Chevrolet Suburban
- 2002 Chevrolet Suburban
- 2003 Chevrolet Suburban
- 2004 Chevrolet Suburban
- 2005 Chevrolet Suburban
- 2006 Chevrolet Suburban
- 2007 Chevrolet Suburban
- 2008 Chevrolet Suburban
- 2009 Chevrolet Suburban
- 2010 Chevrolet Suburban
- 2011 Chevrolet Suburban
- 2012 Chevrolet Suburban
- 2013 Chevrolet Suburban
- 2014 Chevrolet Suburban
Chevrolet Tahoe
- 2000 Chevrolet Tahoe
- 2001 Chevrolet Tahoe
- 2002 Chevrolet Tahoe
- 2003 Chevrolet Tahoe
- 2004 Chevrolet Tahoe
- 2005 Chevrolet Tahoe
- 2006 Chevrolet Tahoe
- 2007 Chevrolet Tahoe
- 2008 Chevrolet Tahoe
- 2009 Chevrolet Tahoe
- 2010 Chevrolet Tahoe
- 2011 Chevrolet Tahoe
- 2012 Chevrolet Tahoe
- 2013 Chevrolet Tahoe
- 2014 Chevrolet Tahoe
Chevrolet Trailblazer SS
- 2006 Chevrolet Trailblazer SS
- 2007 Chevrolet Trailblazer SS
- 2008 Chevrolet Trailblazer SS
- 2009 Chevrolet Trailblazer SS
Pontiac Trans Am
- 1998 Pontiac Trans Am
- 1999 Pontiac Trans Am
- 2000 Pontiac Trans Am
- 2001 Pontiac Trans Am
- 2002 Pontiac Trans Am
GMC Yukon
- 2000 GMC Yukon
- 2001 GMC Yukon
- 2002 GMC Yukon
- 2003 GMC Yukon
- 2004 GMC Yukon
- 2005 GMC Yukon
- 2006 GMC Yukon
- 2007 GMC Yukon
- 2008 GMC Yukon
- 2009 GMC Yukon
- 2010 GMC Yukon
- 2011 GMC Yukon
- 2012 GMC Yukon
- 2013 GMC Yukon
- 2014 GMC Yukon
Vehicle applications reflect the fitment published by Texas Speed & Performance for this part number. Confirm your engine and cylinder head configuration before ordering.
FAQ
What is included in the Texas Speed 427 LSX short block?
It includes a GM LSX iron block, a Texas Speed 4.00" forged crankshaft with 58x reluctor, Texas Speed 6.125" forged I-beam rods, Wiseco forged pistons in the selected -4cc or -13cc dish with upgraded Wiseco wrist pins and ARP main studs, assembled by Texas Speed, plus 12 quarts of break-in oil, an LS engine stand and a shipping crate.
Should I choose the -4cc or -13cc piston for the 427 LSX short block?
The -4cc piston yields a higher compression ratio for a given cylinder head and gasket, while the -13cc dish lowers compression for higher boost or nitrous levels. Texas Speed offers both so the short block can be matched to the fuel and power adder in the build.
How much power is the 427 LSX short block rated for?
Texas Speed rates it for 1200 horsepower and describes it as ideal for large turbocharged, supercharged or nitrous-assisted combinations. Final capability depends on the supporting components, fuel system and tuning.
Which vehicles can use the Texas Speed 427 LSX short block?
It is an LS-architecture short block on the GM LSX iron block, so it fits Gen III and Gen IV LS applications such as 1998 to 2015 Camaro, 1997 to 2013 Corvette, GTO, G8, CTS-V, Chevrolet SS and 1999 to 2014 GM trucks and SUVs, as well as LS swap projects. The 58x reluctor matches Gen IV electronics.
Does the 427 LSX short block use a 24x or 58x reluctor?
The Texas Speed forged crankshaft is fitted with a 58x reluctor wheel to ensure compatibility with Gen IV LS electronics. Buyers running a 24x Gen III controller should confirm crank signal compatibility before ordering.
Is the LSX short block assembled by Texas Speed?
Yes. Texas Speed designs, machines and assembles the 427 LSX short block in-house and ships it with ARP main studs installed, ready for cylinder heads, camshaft and the remaining top-end components.

